Roundel structure for four-compression-chamber diaphragm pump with multiple effects

ABSTRACT

A cylindrical or inverted frustoconical eccentric roundel structure for a four-compression-chamber diaphragm pump includes an annular positioning groove, a vertical or inverted frustoconical flank, and a sloped top ring extending between the annular positioning groove and the vertical or inverted frustoconical flank. By providing the sloped top ring, the oblique high frequency pulling and squeezing phenomenon that occurs in a conventional tubular eccentric roundel is completely eliminated.

This application claims the benefit of provisional U.S. Patent Application No. 62/000,638, filed May 20, 2014, and incorporated herein by reference.

FIELD OF THE PRESENT INVENTION

The present invention relates to a roundel structure for a four-compression-chamber diaphragm pump used in a reverse osmosis (RO) purification system of the type popularly installed on the water supplying apparatus in either a house, recreational vehicle or mobile home, and particularly to a compressing diaphragm pump with a sloped top ring that can eliminate the oblique pulling and squeezing phenomena of the pump so that the service lifespan of the four-compression-chamber diaphragm pump and the durability of key components therein are prolonged.

BACKGROUND OF THE INVENTION

Conventional four-compression-chamber diaphragm pumps are commonly used with reverse osmosis (RO) purifier or RO water purification systems of the type popularly installed on the water supplying apparatus in either a house, recreational vehicle or mobile home The majority of such four-compression-chamber diaphragm pumps, other than the specific type as disclosed in U.S. Pat. No. 6,840,745, can be categorized as similar in design to the four-compression-chamber diaphragm pump shown in FIGS. 1 through 10, which includes a brushed motor 10 with an output shaft 11, a motor upper chassis 30, a wobble plate with an integral protruding cam-lobed shaft 40, an eccentric roundel mount 50, a pump head body 60, a diaphragm membrane 70, four pumping pistons 80, a piston valvular assembly 90 and a pump head cover 20.

The motor upper chassis 30 includes a bearing 31 through which an output shaft 11 of the motor 10 extends. The motor upper chassis 30 also includes an upper annular rib ring 32 with several fastening bores 33 evenly and circumferentially disposed in a rim of the upper annular rib ring 32.

The wobble plate 40 includes a shaft coupling hole 41 through which the corresponding motor output shaft 11 of the motor 10 extends.

The eccentric roundel mount 50 includes a central bearing 51 at the bottom thereof for receiving the corresponding wobble plate 40. Four tubular eccentric roundels 52 are evenly and circumferentially disposed on the eccentric roundel mount 50. Each tubular eccentric roundel 52 has a horizontal top face 53, a female-threaded bore 54 and an annular positioning groove 55 formed in the top face thereof, as well as a rounded shoulder 57 created at the intersection of the horizontal top face 53 and a vertical flank 56.

The pump head body 60 covers the upper annular rib ring 32 of the motor upper chassis 30 to encompass the wobble plate 40 and eccentric roundel mount 50 therein, and includes four operating holes 61 evenly and circumferentially disposed therein. Each operating hole 61 has an inner diameter that is slightly bigger than the outer diameter of the corresponding tubular eccentric roundel 52 in the eccentric roundel mount 50 for respectively receiving the corresponding tubular eccentric roundel 52. A lower annular flange 62 is formed thereunder for mating with corresponding upper annular rib ring 32 of the motor upper chassis 30, and several fastening bores 63 are evenly disposed around a circumference of the pump head body 60.

The diaphragm membrane 70, which is extrusion-molded from a semi-rigid elastic material and placed on the pump head body 60, includes a pair of parallel rims, including outer raised rim 71 and inner raised rim 72, as well as four evenly spaced radial raised partition ribs 73 arranged such that each end of the radial raised partition ribs 73 connects with the inner raised rim 72, thereby forming four equivalent piston acting zones 74 partitioned by the radial raised partition ribs 73. Each piston acting zone 74 has an acting zone hole 75 created therein in correspondence with a respective female-threaded bore 54 in the tubular eccentric roundel 52 of the eccentric roundel mount 50, and an annular positioning protrusion 76 for each acting zone hole 75 is formed at the bottom side of the diaphragm membrane 70 (as shown in FIGS. 8 and 9).

Each pumping piston 80 is disposed in a corresponding one of the corresponding piston acting zones 74 of the diaphragm membrane 70, and has a tiered hole 81 extending therethrough. After each of the annular positioning protrusions 76 in the diaphragm membrane 70 has been inserted into a corresponding annular positioning groove 55 in the tubular eccentric roundel 52 of the eccentric roundel mount 50, respective fastening screws 1 are inserted through the tiered hole 81 of each pumping piston 80 and the acting zone hole 75 of each corresponding piston acting zone 74 in the diaphragm membrane 70, so that the diaphragm membrane 70 and four pumping pistons 80 can be securely screwed into female-threaded bores 54 of the corresponding four tubular eccentric roundels 52 on the eccentric roundel mount 50 (as can be seen in the enlarged portion of FIG. 10).

Piston valvular assembly 90 covers the diaphragm membrane 70 and includes a downwardly extending raised rim 91 for insertion between the outer raised rim 71 and inner raised rim 72 in the diaphragm membrane 70, and a central dish-shaped round outlet mount 92 having a central positioning bore 93 with four equivalent sectors, each of which contains multiple evenly circumferentially-located outlet ports 95. The piston valvular assembly 90 also includes a T-shaped plastic anti-backflow valve 94 with a central positioning shank, and four circumferentially-adjacent inlet mounts 96. Each of the circumferentially-adjacent inlet mounts 96 includes multiple evenly circumferentially-located inlet ports 97 and an inverted central piston disk 98 respectively so that each piston disk 98 serves as a valve for each corresponding group of multiple inlet ports 97. The central positioning shank of the plastic anti-backflow valve 94 mates with the central positioning bore 93 of the central outlet mount 92 such that multiple outlet ports 95 in the central round outlet mount 92 are in communication with the four inlet mounts 96. Finally, a hermetically sealed preliminary-compression chamber 26 is formed between each inlet mount 96 and a corresponding piston acting zone 74 in the diaphragm membrane 70 upon insertion of the downwardly extending raised rim 91 into the gap ring between the outer raised rim 71 and inner raised rim 72 of diaphragm membrane 70, such that one end of each preliminary-compressing chamber 26 is in communication with each of the corresponding inlet ports 97 (as shown in the enlarged portion of FIG. 10).

The pump head cover 20, which covers the pump head body 60 to encompass the piston valvular assembly 90, pumping piston 80 and diaphragm membrane 70 therein, includes a water inlet orifice 21, a water outlet orifice 22, and several fastening bores 23. A tiered rim 24 and an annular rib ring 25 are disposed in the bottom inside of the pump head cover 20 such that the outer rim for the assembly of diaphragm membrane 70 and piston valvular assembly 90 can be hermetically attached to the tiered rim 24 (as shown in the enlarged portion of FIG. 11). A high-compression chamber 27 is formed between the cavity formed by the inside wall of the annular rib ring 25 and the central outlet mount 92 of the piston valvular assembly 90 when the bottom of the annular rib ring 25 closely covers the rim of the central outlet mount 92 (as shown in FIG. 10).

By running each fastening bolt 2 through a corresponding fastening bore 23 of pump head cover 20 and a corresponding fastening bore 63 in the pump head body 60, and then putting a nut 3 onto each fastening bolt 2 to securely screw the pump head cover 20 to the pump head body 60 via the corresponding fastening bores 33 in the motor upper chassis 30, the whole assembly of the four-compression-chamber diaphragm pump is finished (as shown in FIGS. 1 and 10).

Please refer to FIGS. 11 and 12, which are illustrative figures for the operation of the conventional four-compression-chamber diaphragm pump of FIGS. 1-10.

Firstly, when the motor 10 is powered on, the wobble plate 40 is driven to rotate by the motor output shaft 11 so that the four tubular eccentric roundels 52 on the eccentric roundel mount 50 constantly move in a sequential up-and-down reciprocal stroke.

Secondly, in the meantime, the four pumping pistons 80 and four piston acting zones 74 in the diaphragm membrane 70 are sequentially driven by the up-and-down reciprocal stroke of the four tubular eccentric roundels 52 to move in an up-and-down displacement.

Thirdly, when the tubular eccentric roundel 52 moves in a down stroke, causing pumping piston 80 and piston acting zone 74 to be displaced downwardly, the piston disk 98 in the piston valvular assembly 90 is pushed into an open status so that tap water W can flow into the preliminary-compression chamber 26 via water inlet orifice 21 in the pump head cover 20 and inlet ports 97 in the piston valvular assembly 90 (as indicated by the arrowhead extending from W in the enlarged view of FIG. 11);

Fourthly, when the tubular eccentric roundel 52 moves in an up stroke, causing pumping piston 80 and piston acting zone 74 to be displaced upwardly, the piston disk 96 in the piston valvular assembly 90 is pulled into a closed status to compress the tap water W in the preliminary-compression chamber 26 and increase the water pressure therein up to a range of 100 psi-150 psi. The resulting pressurized water Wp causes the plastic anti-backflow valve 94 in the piston valvular assembly 90 to be pushed to an open status.

Fifthly, when the plastic anti-backflow valve 94 in the piston valvular assembly 90 is pushed to an open status, the pressurized water Wp in the preliminary-compression chamber 26 is directed into high-compression chamber 27 via the group of outlet ports 95 for the corresponding sector in the central outlet mount 92, and then expelled out of the water outlet orifice 22 in the pump head cover 20 (as indicated by arrowhead W in the enlarged portion of FIG. 12).

Finally, the sequential iterative action for each group of outlet ports 95 for the four sectors in central outlet mount 92 causes the pressurized water Wp to be constantly discharged out of the conventional four-compression-chamber diaphragm pump to be further RO-filtered by the RO-cartridge so that the final filtered pressurized water Wp can be used in the RO purifier or RO water purification system popularly installed on the water supplying apparatus of either a house, recreational vehicle or mobile home.

Referring to FIGS. 13 and 14, a serious vibration-related drawback has long existed in the conventional four-compression-chamber diaphragm pump. As described previously, when the motor 10 is powered on, the wobble plate 40 is driven to rotate by the motor output shaft 11 so that the four tubular eccentric roundels 52 on the eccentric roundel mount 50 constantly move in a sequential up-and-down reciprocal stroke, and the four piston acting zones 74 in the diaphragm membrane 70 are sequentially driven by the up-and-down reciprocal stroke of the four tubular eccentric roundels 52 to move in up-and-down displacement so that a force F constantly acts on the bottom side of each piston acting zone 74.

Meanwhile a corresponding plurality of rebounding forces Fs are created in reaction to the acting force F exerted on the bottom side of diaphragm membrane 70, with different components distributed over the entire bottom area of each corresponding piston acting zone 74 in the diaphragm membrane 70, as shown in FIG. 14, so that a squeezing phenomenon caused by the rebounding force Fs occurs on a section of the diaphragm membrane 70.

The squeezing phenomenon occurs because, among all of the distributed components of the rebounding force Fs, the maximum component force is exerted at the contacting bottom position P of the diaphragm membrane 70 with the rounded shoulder 57 of the horizontal top face 53 in the tubular eccentric roundel 52 so that the squeezing phenomenon at the bottom position P is also maximum, as shown in FIG. 18.

With the rotational speed for the motor output shaft 11 of the motor 10 reaching a range of 800-1200 rpm, each bottom position P of the piston acting zone 74 of the diaphragm membrane 70 suffers from the squeezing phenomenon at a frequency of four times per second. Under such circumstances, the bottom position P of the diaphragm membrane 70 is always the first broken place for the entire conventional four-compression-chamber diaphragm pump, which is an essential cause of not only shortening the service lifespan but also terminating the normal function of the conventional four-compression-chamber diaphragm pump.

Therefore, how to substantially reduce the drawbacks associated with the squeezing phenomenon caused by the constant application of force F to the bottom side of each piston acting zone 74 of the diaphragm membrane 70 as a result of the movement of the tubular eccentric roundel 52 has also become an urgent and critical issue.

SUMMARY OF THE INVENTION

An objective of the present invention is to provide a roundel structure for a four-compression-chamber diaphragm pump, in which the roundel structure is a cylindrical or inverted frustoconical eccentric roundel disposed on an eccentric roundel mount, and in which the roundel includes an annular positioning groove, a vertical or inverted frustoconical flank, and an annular top surface portion that is inclined relative to horizontal to form a sloped top ring between the annular positioning groove and the vertical or inverted frustoconical flank.

By means of the sloped top ring, the high-frequency oblique pulling and squeezing phenomena that occurs in a conventional tubular eccentric roundel are completely eliminated because the sloped top ring flatly attaches to the bottom area of a corresponding piston acting zone of the diaphragm membrane.

Thus, not only is the durability of the diaphragm membrane enhanced to better withstand the sustained high-frequency pumping action of the eccentric roundels, but the service lifespan of the diaphragm membrane is also greatly prolonged.

Yet another objective of the present invention is to provide an eccentric roundel structure for a four-compression-chamber diaphragm pump, in which the eccentric roundel structure is a cylindrical or inverted frustoconical eccentric roundel disposed on an eccentric roundel mount, and in which the eccentric roundel includes an annular positioning groove, a vertical or inverted frustoconical flank, and a sloped top ring formed between the annular positioning groove and the vertical or inverted frustoconical flank.

Again, by means of the sloped top ring, all distributed components of the rebounding force for the cylindrical eccentric roundels that are generated in reaction to the acting force caused by the pumping action are substantially reduced because the sloped top ring flatly attaches to the bottom area of the corresponding piston acting zone for the diaphragm membrane.

In achieving the above-described objectives, which are not intended to limit the scope of the invention, at least the following benefits are obtained:

1. The durability of the diaphragm membrane for sustaining the high-frequency pumping action of the cylindrical or inverted frustoconical eccentric roundels is substantially enhanced.

2. The power consumption of the four-compression-chamber diaphragm pump is tremendously diminished due to less current being wasted as a result of the above-described high-frequency squeezing phenomena.

3. The working temperature of the four-compression-chamber diaphragm pump is tremendously reduced due to less power consumption.

4. The annoying noise of the bearings that results from aged lubricant in the four-compression-chamber diaphragm pump, which is expeditiously accelerated by the high working temperature, is mostly eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective assembled view of a conventional four-compression-chamber diaphragm pump.

FIG. 2 is a perspective exploded view of a conventional four-compression-chamber diaphragm pump.

FIG. 3 is a perspective view of an eccentric roundel mount for the conventional four-compression-chamber diaphragm pump.

FIG. 4 is a cross sectional view taken against the section line 4-4 from previous FIG. 3.

FIG. 5 is a perspective view of a pump head body for the conventional four-compression-chamber diaphragm pump.

FIG. 6 is a cross sectional view taken against the section line 6-6 from previous FIG. 5.

FIG. 7 is a perspective view of a diaphragm membrane for the conventional four-compression-chamber diaphragm pump.

FIG. 8 is a cross sectional view taken against the section line 8-8 from previous FIG. 7.

FIG. 9 is a bottom view of a diaphragm membrane for the conventional four-compression-chamber diaphragm pump.

FIG. 10 is a cross sectional view taken against the section line 10-10 from previous FIG. 1.

FIG. 11 is a first operation illustrative view of a conventional four-compression-chamber diaphragm pump.

FIG. 12 is a second operation illustrative view of a conventional four-compression-chamber diaphragm pump.

FIG. 13 is a third operation illustrative view of a conventional four-compression-chamber diaphragm pump.

FIG. 14 is a partially enlarged view taken from circled-portion-a of previous FIG. 13.

FIG. 15 is a perspective exploded view of a the first exemplary embodiment of the present invention.

FIG. 16 is a perspective view of an eccentric roundel mount in the first exemplary embodiment of the present invention.

FIG. 17 is a cross sectional view taken against the section line 17-17 from previous FIG. 16.

FIG. 18 is an assembled cross sectional view of the first exemplary embodiment of the present invention.

FIG. 19 is an operation illustrative view of the first exemplary embodiment of the present invention.

FIG. 20 is a partially enlarged view taken from circled-portion-a of previous FIG. 19.

FIG. 21 is an illustrative view showing a comparison between the cylindrical eccentric roundel acting on the diaphragm membrane of the conventional four-compression-chamber diaphragm pump and that of the first exemplary embodiment of the present invention.

FIG. 22 is a perspective view for eccentric roundel mount in the second exemplary embodiment of the present invention.

FIG. 23 is a cross sectional view taken against the section line 23-23 from previous FIG. 22.

FIG. 24 is an assembled cross sectional view for the second exemplary embodiment of the present invention.

FIG. 25 is an operation illustrative view of the second exemplary embodiment of the present invention.

FIG. 26 is a partially enlarged view taken from circled-portion-a of previous FIG. 25.

FIG. 27 is an illustrative view showing a comparison between the cylindrical eccentric roundel acting on the diaphragm membrane for the conventional four-compression-chamber diaphragm pump and for the present invention in the second exemplary embodiment of the present invention.

FIG. 28 is a perspective exploded view for the third exemplary embodiment of the present invention.

FIG. 29 is a cross sectional view taken against the section line 29-29 from previous FIG. 28.

FIG. 30 is a perspective assembled view for the third exemplary embodiment of the present invention.

FIG. 31 is a cross sectional view taken against the section line 31-31 from previous FIG. 30.

FIG. 32 is an assembled cross sectional view for the third exemplary embodiment of the present invention.

FIG. 33 is an operation illustrative view for the third exemplary embodiment of the present invention.

FIG. 34 is a partially enlarged view taken from circled-portion-a of previous FIG. 33.

FIG. 35 is an illustrative view showing a comparison between the cylindrical eccentric roundel acting on the diaphragm membrane for the conventional four-compression-chamber diaphragm pump and for the present invention in the third exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 15 through 18 are illustrative figures of a roundel structure for four-compression-chamber diaphragm pump according to a first exemplary embodiment of the present invention.

The roundel structure is a cylindrical eccentric roundel 52 mounted on the eccentric roundel mount 50. The cylindrical eccentric roundel includes an annular top surface portion that is inclined relative to horizontal to form a sloped top ring 58 between the annular positioning groove 55 and a vertical flank 56, the sloped top ring 58 replacing the conventional rounded shoulder 57 in each tubular eccentric roundel 52 of the eccentric roundel mount 50.

FIGS. 19 through 21 are illustrative figures for the operation of the roundel structure for four-compression-chamber diaphragm pump” in the first exemplary embodiment of the present invention.

Firstly, when the motor 10 is powered on, the wobble plate 40 is driven to rotate by the motor output shaft 11 so that the four cylindrical eccentric roundels 52 on the eccentric roundel mount 50 constantly move in a sequential up-and-down reciprocal stroke.

Secondly, four piston acting zones 74 in the diaphragm membrane 70 are sequentially driven by the up-and-down reciprocal stroke of four cylindrical eccentric roundels 52 to move in up-and-down displacement.

Thirdly, when the tubular eccentric roundel or cylindrical eccentric roundel 52 moves in an up stroke with the piston acting zone 74 in an upward displacement, an acting force F will obliquely pull on the partial portion between the corresponding annular positioning protrusion 76 and outer raised rim 71 of the diaphragm membrane 70.

By comparing the operation of the conventional tubular eccentric roundels 52 shown in FIG. 14 and the cylindrical eccentric roundels 52 of the present invention, as illustrated in FIG. 20, at least the following two differences are evident:

In the case of conventional tubular eccentric roundel 52 shown in FIG. 14, the maximum among all of the distributed components Fs of the rebounding force is the component force exerted at the contacting bottom position P of the diaphragm membrane 70, which is located at an edge of the rounded shoulder 57 on a horizontal top face 53 of tubular eccentric roundel 52, so that the “squeezing phenomenon” at point P is also maximum. With such nonlinear distribution of the “squeezing phenomena,” the obliquely pulling action becomes severe. In contrast, in the case of cylindrical eccentric roundels 52 as illustrated in FIG. 20, the distribution of components of the rebounding force Fs is more linear because the sloped top ring 58 therein flatly attaches to the bottom area of the piston acting zone 74 for the diaphragm membrane 70, so that the oblique pulling action is almost eliminated due to reduction in the squeezing phenomenon.

Moreover, under the same acting force F, the rebounding force Fs is inversely proportional to the contact area so that the magnitudes of the distributed components of the rebounding force Fs for the cylindrical eccentric roundels 52 of the present invention, as shown in FIG. 20, are substantially less than the magnitudes of the distributed components of the rebounding force Fs for the conventional tubular eccentric roundel 52 shown in FIG. 14.

The improved distribution linearity and decreased magnitudes of the rebounding force components Fs are the result of forming the sloped top ring 58 between the annular positioning groove 55 and the vertical flank 56 in the eccentric roundel mount 50, and in turn provides at least the following two advantages. First, the improved force component distribution eliminates susceptibility to breakage of the diaphragm membrane 70 caused by the high frequency squeezing phenomena, that occurs in the conventional arrangement as a result of the rounded shoulder 57 in the otherwise horizontal top face 53 of the tubular eccentric roundel52. Second, because of the decrease in magnitude of the rebounding force components, the overall rebounding force Fs of the diaphragm membrane 70 caused by the acting force F during sequential up-and-down displacement of the four piston acting zones 74 in the diaphragm membrane 70 driven by the up-and-down reciprocal stroke of the four tubular eccentric roundels or cylindrical eccentric roundels 52 is tremendously reduced.

These advantages result in the following practical benefits:

1. The durability of the diaphragm membrane 70 for sustaining the high frequency pumping action of the cylindrical eccentric roundels 52 is substantially enhanced.

2. The power consumption of the four-compression-chamber diaphragm pump is tremendously diminished due to less current being wasted as a result of the squeezing phenomena at high frequencies.

3. The working temperature of the four-compression-chamber diaphragm pump is tremendously reduced due to the decrease in power consumption.

4. The undesirable bearing noise caused by aging of the lubricant in the four-compression-chamber diaphragm pump, which is normally accelerated by the high working temperature, is mostly eliminated.

Test results carried out on a prototype of the present invention are as follows.

A. The service lifespan of the tested diaphragm membrane 70 was more than doubled.

B. The reduction in electric current consumption exceeded 1 ampere.

C. The working temperature was reduced by over 15 degrees Celsius.

D. The smoothness of the bearing was improved.

Please refer to FIGS. 22 through 24, which are illustrative figures of a roundel structure for four-compression-chamber diaphragm pump in the second exemplary embodiment of the present invention, the roundel structure is an inverted frustoconical eccentric roundel 502, again provided on an eccentric roundel mount 500.

The frustoconical eccentric roundel 502 includes an integral inverted frustoconical flank 506 and a sloped top ring 508 such that the outer diameter of the frustoconical eccentric roundel 502 is enlarged but still smaller than the inner diameter of the operating hole 61 in the pump head body 60, the sloped top ring 508 extending between an annular positioning groove 505 and the inverted frustoconical flank 506.

FIGS. 25 through 27 are illustrative figures showing the operation of the “roundel structure for four-compression-chamber diaphragm pump” in the second exemplary embodiment of the present invention.

Firstly, when the motor 10 is powered on, the wobble plate 40 is driven to rotate by the motor output shaft 11 so that the four frustoconical eccentric roundels 502 on the eccentric roundel mount 500 constantly move in a sequential up-and-down reciprocal stroke.

Secondly, the four piston acting zones 74 in the diaphragm membrane 70 are sequentially driven by the up-and-down reciprocal stroke of the four frustoconical eccentric roundels 502 to move in up-and-down displacement.

Thirdly, when the frustoconical eccentric roundel 502 in the present invention moves in an up stroke so that the corresponding piston acting zone 74 is displaced upwardly, the acting force F will obliquely pull the partial portion between the corresponding annular positioning protrusion 76 and outer raised rim 71 of the diaphragm membrane 70.

Consequently, the inclusion of the sloped top ring 508 in the eccentric roundel mount 500 eliminates breakage of the diaphragm membrane 70 caused by the high frequency squeezing phenomena and also causes the rebounding force Fs of the diaphragm membrane 70 caused by the acting force F to be tremendously reduced. Meanwhile, by means of the inverted frustoconical flank 506, the possibility of collision between the frustoconical eccentric roundel 502 and the operating hole 61 in the pump head body 60 is eliminated even though the outer diameter of the frustoconical eccentric roundel 502 is enlarged.

Moreover, under the same acting force F, the rebounding force Fs is inversely proportional to the contact area. By means of the enlarged outer diameter of the inverted frustoconical eccentric roundel 502, the contact area of the sloped top ring 508 with the bottom side of the diaphragm membrane 70 is increased (as indicated by ring A shown in FIG. 27) so that all distributed components of the rebounding force Fs for the inverted frustoconical eccentric roundels 502 of the present invention are further reduced.

The inverted frustoconical eccentric roundel 502 of this embodiment of the present invention therefore provides at least some of the following benefits:

1. The durability of the diaphragm membrane 70 for sustaining the high frequency pumping action is substantially increased as a result of the inverted frustoconical eccentric roundel 502.

2. The power consumption of the four-compression-chamber diaphragm pump is tremendously diminished due to less current being wasted as a result of the high frequency squeezing phenomena.

3. The working temperature of the four-compression-chamber diaphragm pump is tremendously reduced due to less power consumption.

4. The undesirable bearing noise resulting from aged lubricant in the four-compression-chamber diaphragm pump, which is exacerbated by accelerated aging due to a high working temperature, is mostly eliminated.

5. The service lifespan of the four-compression-chamber diaphragm pump is further prolonged because all distributed components of the rebounding force Fs for the inverted frustoconical eccentric roundels 502 of the present invention are reduced.

FIGS. 28 through 31 are illustrative figures of eccentric roundel structure for four-compression-chamber diaphragm pump in the third exemplary embodiment of the present invention, in which the eccentric roundel structure is a combinational eccentric roundel 502 in an eccentric roundel mount 500. The combinational eccentric roundel 502 includes a roundel mount 511 and an inverted frustoconical roundel yoke 521 in detachable separation such that the outer diameter of the frustoconical roundel yoke 521 is enlarged but still smaller than the inner diameter of the operating hole 61 in the pump head body 60. In this embodiment, the roundel mount 511 has two layers that include a bottom-layer base with a positioning crescent surface 512 facing inwardly and a top-layer protruding cylinder 513 with a central female-threaded bore 514. The inverted frustoconical roundel yoke 521 is sleeved over the corresponding roundel mount 511 and includes an upper bore 523, a middle bore 524 and a lower bore 525 stacked as a three-layered integral hollow structure, as well as an inverted frustoconical flank 522 and a sloped top ring 526 extending from the upper bore 523 to the inverted frustoconical flank 522 such that the bore diameter of the upper bore 523 is bigger than the outer diameter of the protruding cylinder 513. The bore diameter of the middle bore 524 is approximately equal to the outer diameter of the protruding cylinder 513, such that the bore diameter of the lower bore 525 is approximately equal to the outer diameter of the bottom-layer base in the roundel mount 511, and such that the crescent engages a corresponding surface of the lower bore to prevent relative rotation of the roundel yoke 521 and the corresponding roundel mount 511. A positioning annular groove 515 is formed between the protruding cylinder 513 and the inside wall of the upper bore 523 when the frustoconical roundel yoke 521 is sleeved over the roundel mounts 511 (as shown in FIGS. 30 and 31).

FIGS. 32 and 35 illustrate the manner in which the roundel structure for four-compression-chamber diaphragm pump third exemplary embodiment of the present invention is assembled.

Firstly, the frustoconical roundel yoke 521 is fitted over the roundel mounts 511.

Secondly, all four annular positioning protrusions 76 of the diaphragm membrane 70 are inserted into four corresponding positioning annular grooves 515 in the four combinational eccentric roundels 502 of the eccentric roundel mount 500.

Finally, each fastening screw 1 is inserted through a corresponding tiered hole 81 of the pumping piston 80 and each corresponding acting zone hole 75 in the piston acting zones 74 of the diaphragm membrane 70, and then the fastening screw 1 is securely screwed into the four corresponding female-threaded bores 514 in the four roundel mounts 511 of the eccentric roundel mount 500 to firmly assembly the diaphragm membrane 70 and four pumping pistons 80 (as shown in FIG. 32).

FIGS. 33 and 34 illustrate the operation of the above-described the roundel structure for four-compression-chamber diaphragm pump of the third exemplary embodiment of the present invention.

Firstly, when the motor 10 is powered on, the wobble plate 40 is driven to rotate by the motor output shaft 11 so that four combinational eccentric roundels 502 on the eccentric roundel mount 50 constantly move in a sequential up-and-down reciprocal stroke.

Secondly, the four piston acting zones 74 in the diaphragm membrane 70 are sequentially driven by the up-and-down reciprocal stroke of the four combinational eccentric roundels 502 to move in up-and-down displacement.

Thirdly, when the combinational eccentric roundel 502 in the present invention moves in an up stroke to displace the piston acting zone 74 upwardly, the acting force F will obliquely pull the partial portion between the corresponding annular positioning protrusion 76 and the outer raised rim 71 of the diaphragm membrane 70.

Consequently, the inclusion of the sloped top ring 526 in the inverted frustoconical roundel yoke 521 of the eccentric roundel mount 500 eliminates susceptibility to breakage of the diaphragm membrane 70 caused by the high frequency squeezing phenomena (as shown in FIGS. 33 and 34) and also causes the rebounding force Fs of the diaphragm membrane 70 caused by the acting force F to be tremendously reduced (as shown in FIG. 34).

Moreover, under the same acting force F, the rebounding force Fs is inversely proportional to the contact area. By means of the enlarged outer diameter of the inverted frustoconical roundel yoke 521, the contact area of the sloped top ring 508 with the bottom side of the diaphragm membrane 70 is increased (as indicated by ring A shown in FIG. 35) so that all distributed components of the rebounding force Fs for the inverted frustoconical roundel yoke 521 of the present invention are further reduced.

The fabrication of the roundel structure for four-compression-chamber diaphragm pump of the third exemplary embodiment of the present invention is as follows:

Firstly, the roundel mount 511 and eccentric roundel mount 500 are fabricated together as an integral body.

Secondly, the frustoconical roundel yoke 521 is independently fabricated as a separate entity.

Finally, the frustoconical roundel yoke 521 and the integral body of the roundel mount 511 are assembled with eccentric roundel mount 500 to become a united entity and form the assembled eccentric roundel 502 best shown in FIGS. 108 and 109.

Thereby, the contrivance of the combinational eccentric roundel 502 not only meets the requirement of mass production but also reduces the overall manufacturing cost.

The eccentric roundel 502 with frustoconical roundel yoke 521 of the present invention provides at least some of the following benefits:

1. The durability of the diaphragm membrane 70 for sustaining the high frequency pumping action is substantially increased by including the inverted frustoconical roundel yoke 521.

2. The power consumption of the four-compression-chamber diaphragm pump is tremendously reduced due to less current being wasted as a result of the high frequency squeezing phenomena.

3. The working temperature of the four-compression-chamber diaphragm pump is tremendously reduced due to the reduction in power consumption.

4. The undesired bearing noise resulting from temperature-accelerated aging of the lubricant in the four-compression-chamber diaphragm pump is mostly eliminated.

5. The service lifespan of the four-compression-chamber diaphragm pump is further prolonged because all distributed components of the rebounding force Fs for the inverted frustoconical roundel yoke 521 of the present invention are further reduced.

6. The manufacturing cost of the four-compression-chamber diaphragm pump is reduced because the present invention is suitable for mass production.

The illustrated embodiments of the invention thus provide a cylindrical eccentric roundel 52, an inverted frustoconical eccentric roundel 502, or combinational eccentric roundel 502 that, among other advantages, increases the service lifespan of the diaphragm membrane 70 so that the service lifespan of the four-compression-chamber diaphragm pump can be doubled. 

What is claimed is:
 1. A roundel structure for a four-compression-chamber diaphragm pump, said roundel structure including a roundel mount situated on a lower side of a pump head body and four eccentric roundels mounted on the roundel mount to extend through four operating holes in the pump head body, said four-compression-chamber diaphragm pump having a motor with a motor housing to which the pump head body is fixed, a diaphragm membrane fixed to the four eccentric roundels through the four operating holes and situated on an upper side of the pump head body, and four pumping pistons arranged to be moved in a pumping action upon movement of the diaphragm membrane, the roundel mount engaging a wobble plate such that rotation of the wobble plate by the motor causes the roundel mount to wobble, resulting in sequential up and down movement of the four eccentric roundels, the sequential up and down movement of the eccentric roundels causing sequential, reciprocating movement of four piston acting zones in the diaphragm member and the four pumping pistons, and the diaphragm membrane further including four annular downwardly-projecting positioning protrusions each arranged to be inserted into a respective annular positioning groove in a top surface of each of said eccentric roundels, wherein: a section of the top surface of each eccentric roundel is inclined relative to horizontal to form a sloped top ring between a respective said annular positioning groove and a vertical or inverted frustoconical flank of the respective eccentric roundel.
 2. A roundel structure for a four-compression-chamber diaphragm pump as claimed in claim 1, wherein said eccentric roundel mount includes a central bearing for receiving an integral cam-lobed shaft of the wobble plate to enable said sequential up and down movement of the four eccentric roundels in response to rotation of the wobble plate by the motor.
 3. A roundel structure for a four-compression-chamber diaphragm pump as claimed in claim 1, wherein: said pump head body is secured to the motor housing to encompass the wobble plate and eccentric roundel mount therein; said diaphragm membrane is made of a semi-rigid elastic material and placed on the pump head body, said diaphragm membrane including at least one raised rim as well as a plurality of evenly spaced radial raised partition ribs connected with the at least one raised brim to form said four piston acting zones, and each piston acting zone has an acting zone hole formed therein at a position corresponding to a position of a fastening bore in a respective one of the eccentric roundels, and each pumping piston has a tiered hole such that a fastening member extends through the tiered hole, through the acting zone hole of each corresponding piston acting zone in the diaphragm membrane, and into a respective fastening hole in a respective one of the eccentric roundels to secure the diaphragm membrane and each of the pumping pistons to the corresponding eccentric roundels in the eccentric roundel mount.
 4. A roundel structure for a four-compression-chamber diaphragm pump as claimed in claim 3, wherein said four-compression-chamber diaphragm pump further includes: a piston valvular assembly that covers the diaphragm membrane and is peripherally secured to the diaphragm membrane by sealing engagement, the piston valvular assembly including a central outlet mount having a central positioning bore and a plurality of equivalent sectors, each of which contains multiple evenly circumferentially-located outlet ports, a T-shaped plastic anti-backflow valve with a central positioning shank, and a plurality of circumferential inlet mounts, each of each of the inlet mounts including multiple evenly circumferentially-located inlet ports and an inverted central piston disk mounted to the respective inlet mount so that each piston disk serves as a valve for each corresponding group of multiple inlet ports, wherein the central positioning shank of the plastic anti-backflow valve mates with the central positioning bore of the central outlet mount such that said multiple outlet ports in the central round outlet mount communicate with the plurality of inlet mounts, and a hermetic preliminary water-pressurizing chamber is formed in each inlet mount and corresponding piston acting zone in the diaphragm membrane upon the diaphragm membrane being peripherally secured to the piston valvular assembly such that one end of each of the preliminary water-pressuring chamber is communicable with each corresponding one of said inlet ports; and a pump head cover, which covers the pump head body to encompass the piston valvular assembly, pumping pistons and diaphragm membrane therein, includes a water inlet orifice, and a water outlet orifice, said pump head cover being hermetically attached to the assembly of diaphragm membrane and piston valvular assembly to form a high-pressured water chamber between a cavity formed by an inside wall of an annular rib ring and the central outlet mount of the piston valvular assembly.
 5. A roundel structure for a four-compression-chamber diaphragm pump as claimed in claim 1, wherein each said eccentric roundel is a cylindrical eccentric roundel.
 6. A roundel structure for a four-compression-chamber diaphragm pump as claimed in claim 1, wherein each said eccentric roundel is an inverted frustoconical eccentric roundel, and wherein a largest diameter of the inverted frustoconical eccentric roundel is smaller than an inner diameter of a corresponding one of said operating holes in the pump head body.
 7. A roundel structure for a four-compression-chamber diaphragm pump as claimed in claim 6, wherein said inverted frustoconical eccentric roundels each includes a mounting portion fixed to the roundel mount and a separable inverted frustoconical roundel yoke mounted on the roundel mount to form a two-layered eccentric roundel structure.
 8. A roundel structure for a four-compression-chamber diaphragm pump as claimed in claim 7, wherein the mounting portion of each of the inverted frustoconical eccentric roundels is integrally fabricated with the roundel mount, and the inverted frustoconical roundel yokes are separately fabricated.
 9. A roundel structure for a four-compression-chamber diaphragm pump as claimed in claim 6, wherein a mounting portion of each of the inverted frustoconical eccentric roundels includes a base with an inwardly-facing positioning surface and a cylinder with a central female-threaded bore extending upwardly from the base, and wherein each of the inverted frustoconical yokes includes an upper bore, a middle bore, and a lower bore, wherein a diameter of the middle bore is approximately equal to a diameter of the mounting portion cylinder, a diameter of the upper bore is larger than the diameter of the mounting portion cylinder, and a diameter of the lower bore is approximately equal to a diameter of the mounting portion base, said lower bore being fitted over the base, said middle bore being sleeved over the cylinder, and said annular positioning groove being defined by a space between said cylinder and an inner wall of said upper bore.
 10. A roundel structure for a four-compression-chamber diaphragm pump as claimed in claim 1, wherein said motor is a brushed motor.
 11. A roundel structure for a four-compression-chamber diaphragm pump as claimed in claim 1, wherein said motor is a brushless motor. 